<template>
  <div class="app-container">
    <h2 style="text-align: center;">发布新课程</h2>

    <el-steps :active="1" process-status="wait" align-center style="margin-bottom: 40px;">
      <el-step title="填写课程基本信息" />
      <el-step title="创建课程大纲" />
      <el-step title="提交审核" />
    </el-steps>

    <el-form label-width="120px">
      <el-form-item label="课程标题">
        <el-input v-model="courseInfo.title" placeholder=" 示例：机器学习项目课：从基础到搭建项目视频课程。专业名称注意大小写" />
      </el-form-item>

      <!-- 所属分类 TODO -->
      <!-- 所属分类：级联下拉列表 -->
      <!-- 一级分类 -->
      <el-form-item label="课程类别">
        <el-select
          v-model="courseInfo.subjectParentId"
          placeholder="请选择"
          @change="subjectLevelOneChanged"
        >
          <el-option
            v-for="subject in subjectNestedList"
            :key="subject.id"
            :label="subject.title"
            :value="subject.id"
          />
        </el-select>
        <!-- 二级分类 -->
        <el-select v-model="courseInfo.subjectId" placeholder="请选择">
          <el-option
            v-for="subject in subSubjectList"
            :key="subject.value"
            :label="subject.title"
            :value="subject.id"
          />
        </el-select>
      </el-form-item>

      <!-- 课程讲师 -->
      <el-form-item label="课程讲师">
        <el-select v-model="courseInfo.teacherId" placeholder="请选择">
          <el-option
            v-for="teacher in teacherList"
            :key="teacher.id"
            :label="teacher.name"
            :value="teacher.id"
          />
        </el-select>
      </el-form-item>
      <el-form-item label="总课时">
        <el-input-number
          :min="0"
          v-model="courseInfo.lessonNum"
          controls-position="right"
          placeholder="请填写课程的总课时数"
        />
      </el-form-item>

      <!-- 课程简介 TODO -->
      <!-- 课程简介-->
      <el-form-item label="课程简介">
        <tinymce :height="300" v-model="courseInfo.description" />
      </el-form-item>

      <!-- 课程封面 TODO -->
      <!-- 课程封面-->
      <el-form-item label="课程封面">
        <el-upload
          :show-file-list="false"
          :on-success="handleAvatarSuccess"
          :before-upload="beforeAvatarUpload"
          :action="BASE_API+'/oss/ossFile?host=cover'"
          class="avatar-uploader"
        >
          <img :src="courseInfo.cover" />
        </el-upload>
      </el-form-item>
      <el-form-item label="课程价格">
        <el-input-number
          :min="0"
          v-model="courseInfo.price"
          controls-position="right"
          placeholder="免费课程请设置为0元"
        />元
      </el-form-item>

      <el-form-item>
        <el-button :disabled="saveBtnDisabled" type="primary" @click="next">保存并下一步</el-button>
      </el-form-item>
    </el-form>
  </div>
</template>

<script>
import course from "@/api/edu/course";
import subject from "@/api/edu/subject";
import Tinymce from "@/components/Tinymce";

const defaultForm = {
  title: "",
  subjectId: "", // 一级分类
  subjectParentId: "", // 二级分类
  teacherId: "",
  lessonNum: 0,
  description: "",
  cover: "/static/test.jpg",
  price: 0
};

export default {
  components: { Tinymce },
  data() {
    return {
      teacherList: [],
      subjectNestedList: [], //一级分类列表
      subSubjectList: [], //二级分类列表
      courseInfo: defaultForm,
      courseId: "",
      BASE_API: process.env.BASE_API, // 接口API地址
      saveBtnDisabled: false // 保存按钮是否禁用
    };
  },
  watch: {
    $route(to, from) {
      console.log("watch $route");
      this.init();
    }
  },

  created() {
    console.log("info created");
    this.init();
  },

  methods: {
    // 上传成功之后的函数
    handleAvatarSuccess(res, file) {
      console.log(res); // 上传响应
      console.log(URL.createObjectURL(file.raw)); // base64编码
      this.courseInfo.cover = res.data.fileUrl;
    },
    // 上传图片前的函数
    beforeAvatarUpload(file) {
      const isJPG = file.type === "image/jpeg";
      const isLt2M = file.size / 1024 / 1024 < 2;
      if (!isJPG) {
        this.$message.error("上传头像图片只能是 JPG 格式!");
      }
      if (!isLt2M) {
        this.$message.error("上传头像图片大小不能超过 2MB!");
      }
      return isJPG && isLt2M;
    },

    // 初始化一级分类
    initOneSubjectList() {
      subject.getNestedTreeList().then(response => {
        this.subjectNestedList = response.data.items;
      });
    },
    // 获取讲师列表
    getTeacherList() {
      course
        .getTeacherList()
        .then(response => {
          this.teacherList = response.data.items;
        })
        .catch(error => {});
    },

    // 初始化
    init() {
      if (this.$route.params && this.$route.params.id) {
        const id = this.$route.params.id;
        console.log(id);
        //根据id获取课程基本信息
        this.fetchCourseInfoById(id);
      } else {
        this.courseInfo = { ...defaultForm };
        // 初始化分类列表
        this.initOneSubjectList();
        // 获取讲师列表
        this.getTeacherList();
      }
    },
    // 下一步
    next() {
      console.log("next");
      this.saveBtnDisabled = true;
      if (!this.courseInfo.id) {
        this.saveData();
      } else {
        this.updateData();
      }
    },

    // 保存
    saveData() {
      course
        .saveCourseInfo(this.courseInfo)
        .then(response => {
          this.$message({
            type: "success",
            message: "保存成功!"
          });
          return response; // 将响应结果传递给then
        })
        .then(response => {
          // 跳转页面
          debugger;
          console.log(23424324324);
          this.$router.push({
            path: "/course/chapter/" + response.data.courseId
          });
        })
        .catch(response => {
          this.$message({
            type: "error",
            message: response.message
          });
        });
    },
    // 更新
    updateData() {
      this.saveBtnDisabled = true;
      course
        .updateCourseInfoById(this.courseInfo)
        .then(response => {
          this.$message({
            type: "success",
            message: "修改成功!"
          });
          return response; // 将响应结果传递给then
        })
        .then(response => {
          this.$router.push({
            path: "/course/chapter/" + response.data.courseId
          });
        })
        .catch(response => {
          // console.log(response)
          this.$message({
            type: "error",
            message: "保存失败"
          });
        });
    },
    // 点击一级分类  触发二级分类的事件
    subjectLevelOneChanged(value) {
      console.log(value);
      for (let i = 0; i < this.subjectNestedList.length; i++) {
        if (this.subjectNestedList[i].id === value) {
          this.subSubjectList = this.subjectNestedList[i].children;
          this.courseInfo.subjectId = "";
        }
      }
    },
    fetchCourseInfoById(id) {
      course
        .getCourseInfoById(id)
        .then(responseCourse => {
          this.courseInfo = responseCourse.data.item;
          // 初始化分类列表
          subject.getNestedTreeList().then(responseSubject => {
            this.subjectNestedList = responseSubject.data.items;
            for (let i = 0; i < this.subjectNestedList.length; i++) {
              if (
                this.subjectNestedList[i].id === this.courseInfo.subjectParentId
              ) {
                this.subSubjectList = this.subjectNestedList[i].children;
              }
            }
          });
          // 获取讲师列表
          this.getTeacherList();
        })
        .catch(response => {
          this.$message({
            type: "error",
            message: response.message
          });
        });
    }
  }
};
</script>


<style scoped>
.tinymce-container {
  line-height: 29px;
}
</style>